An accuracy of subsurface utility mapping by ground penetrating radar imaging

Abstract

Subsurface utility mapping is important for extracting information of buried utility features such as electric and telephone cables, gas pipe, sewerage pipes and the water reticulation pipes. Ground penetrating radar (GPR) has been widely used for subsurface utility mapping in extracting depth of the buried utility features. In most practices of subsurface utility mapping with GPR, perpendicular-scan lines to features orientation scanning are used. This paper highlights the results of study undertaken in investigating the effects of GPR scanning approaches to the accuracy of subsurface utility mapping by using the GPR imaging. Three different survey techniques examined are: (i) perpendicular scanning, (ii) parallel to pipe scanning and (iii) variation angles scanning. The GPR data acquisition were carried out over known GPR test sites with the different scanning approaches are subjected to pre-processing and feature identification. Parallel-to-pipe scanning reports the optimal accuracy of the feature location, apart from better penetrative power. Hence, results of this study is vital in improving the good practice for data acquisition as data quality is of paramount importance for further processing work in most subsurface utility mapping practices.